4-*> Mr. Hersciikl's Catakgue 
L iirft luipe6led a reparation ' and November 13th, fairly 
faw a divifion between them. April 4, 1783, with an 
improved refledtor of 20 feet 3 inches focal length and 
12 inches aperture, I faw them evidently divided. Por- 
tion 20° 54 / f. following*. 
Zj. Fl. 90 Leonis. Infra edudlionem caud^. 
Feb. 9. Treble. The two neareft — very unequal. L. w. ; 
1782. S. rw. With 278, diameter of L ; with 460, if 
diameter of L. Polition with 278, 6 1° 9' f. preceding. 
The two fartheft — very unequal. S. dufky r. Dif- 
tance from L. S 3 " ^ 3 '" • Portion 35° 12' f. preceding. 
Leonis. Fl 41. In collo lucida. 
Ftb. 11. A beautiful double ftar. Pretty unequal. L. w. ; 
17S2. S. w. inclining a little to pale red. With 227 and 278 
diftindtty feparated ; with 460, 4. diameter of S. ; with 
625, l diameter; with 932, full | diameter, or when 
* I fufpeft- thefe ftars to recede from each other. It is, however, very 
pofiible, that the opening which I obferved between them, at the latter end 
of the year 1782 and beginning of 1783, may be owing to very favoura- 
ble weather, or to my being better acquainted with the objett. Could we 
increafe our power and ditlindlnefs at plcafure, we might undoubtedly feparate 
any two ftars that are not abfolutely in a direct line palling through the eye of the 
observer, and the centers of both the ftars. This will appear when we confider 
that perhaps 59 thirds out of one fecond, which the diameter of the ftar may 
fubtend, are fpurious ; fo that a double ftar feemingly in contact, or even partly 
hiding each other in appearance, may ftill be far enough aiunder to admit of a fair 
and considerable reparation by applying an adequate magnifying power. It would 
have been curious, if a confiderable difference in the colours could have led us to 
d tfcover which of the two ftars is before the other ! But the far greateft part of 
their apparent diameters being, as we have obferved, fpurious, it is probable, that 
a different coloured light of two ftars would join together, where the rays of one 
extend into thofe of the other ; and fo, producing a third colour by the mixture 
•of it, ftill leave the queftion undecided. 
